Drop-hammer-operating means



Patented June 20, I899.

F. A. PRATT.

DROP HAMMER OPERATING MEANS.

(Application filed Oct. 28, 1898.) (No Model.) 2 Sheets-Sheefi l.

Witnesses: In winter.-

THE scams PETERS co PHQTO-LITHCL, WASHINGTON. u. c.

Patented lune 2o, I899. F. A. PRATT.

DROP HAMMER OPERATING mums.

(Application filed Oct. 28, 1898.)

2 Sheets-Sheet 2.

(No Model.)

I72 2/622 for:

m a e m A as ATENTC Orrrcn.

' DROP-HAMMER-OPERATING MEANS.

SPECIFICATION forming part of Letters Patent No. 627,349, dated June 20, 1899.

Application filed October 28,1898. Serial No. 694,808- (No model.)

To all whom it may concern.-

Be it known that I, FRANCIS A. PRATT, a citizen of the United States, residing at Hartford, in the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in Drop-Hammer-Opcrating Means, of which the following is a specification.

To satisfactorily drop-forge many kinds of work, it is necessary to subject the metal to repeated blows of uniform force, and to ac complish this drop hammers are provided with automatically operating mechanism. Certain classes of work can be forged by a single or but a few drops, and for this purpose drop-hammers are arranged to be controlled by the foot of the operative. Often it is desirable to commence forging with a number of rapid blows of uniform power and in finishing to modify the action and effect lighter blows, and this requires a shifting from the automatic to the foot controlling mechanisms.

This invention relates to the means which are utilized for setting in operation the mechanisms of those drop-hammers which are arranged so that the blows may be automatically repeated with uniform force or may be controlled by the foot of the operative for striking one or more blows of varying force more or less rapidly.

The object of the invention is the production of a very simple means for drop-hamm ers of this class, whereby the dropping. of the hammer either automatically or singly is controlled by the foot of the operative and the change from one to the other is efiected by a convenient movement of the foot from one part to another.

The drop-hammer that is illustrated in the accompanying drawings as embodying the invention has contin uously-rotatin g rolls so supported at the top of the standards,which above the bed form the guideway for the hammerhead, that theyare at the end of the drop of the hammer-head caused to grip the tail-board and lift the hammer-head and at the end of the lift caused to release the tail-board, so that the hammer-head is free to drop if it is not held by a catch-lever. The mechanisms for moving the rolls are connected with a compound treadle that is so constructed that when one part is made use of the catch-lever only is manipulated and the hammer-head allowed to drop and be lifted automatically;

but when the other part is utilized the catchthe bed 2 at the top, arejoined bya cap 3, and

the hammer-head 4.,with one of the dies,is mov able toward and from the bed that supports the other die in a guideway formed between the standards. The tail-board 5 projects from the hammerhead in a common manner between rolls 6, mounted on shafts provided with driving-pulleys 7. The bearings for the front roll-shaft are formed at the upper end of a swinging plate 8, that is pivotally supported 1 by the cap, and the lower end of this plate is joined with the upper end of a vertical shaft 9 by an eccentric connection 10. The vertical shaft is supported by brackets 11, secured to the front of one of the standards, and projecting from the lower end is an arm 12, that is connected by a hook 13 with an angle-lever 14. A spring 15 is attached to this lever and to the standard in such manner that the lever tends to rock the arm and impart to the shaft such a rotative movement that through the eccentric connection the swinging plate will be moved and the front roll forced against the face of the tail-board. When the parts are free to be moved in this manner,the tail-board is gripped and elevated by the rotating rolls.

Adjustably fastened to the vertical shaft is a cam 16, and projecting from the hammerhead, so that when lifted it will engage this cam and impart a rotative movement to the shaft, is a stud 17. When the stud engages the cam and rotates the shaft, the swinging plate is so moved that the front roll which it bears is carried away from the tail-board. The cam is fastened to the shaftin such position that at the time the hammer-head reaches the desired height the parts are moved sufficiently to release the grip of the roll on the tail-board. The amount of upward movement, and consequently the force of the drop of the hammer, can be regulated by adjusting the cam along the verticaFshaft.

The catch-lever 18, which is held by a pin 19 thrust into either of a number of sockets 20, engages a recess as the grip of the liftingrolls is released and prevents the hammerhead from dropping. The outer end of the catch-lever is yieldingly connected with the rod 21.

About the instant the descending hammer strikes a working blow a wedge 22, connected with the hammer, engages and moves a finger 23, projecting from a rock-shaft 24, supported adjacent to the lower end of the vertical shaft. This rock-shaft bears a latch 25, which is simply a finger with a hooked end that is arranged to catch over a rib 26, extending from the vertical shaft when that shaft is given a rotative movement by the engagement with its cam of the stud on the hammer-head, so that the rib will pass into engagement with the latch. Aspring27 tends to throw the rockshaft so that the latch will catch the lockingrib and hold the vertical shaft from rotative movement with the spring under tension until the rock-shaft and latch are given a rotative movement by the drop of the hammer. The latch may be provided with an eye, and a hook 41 may be attached to the standard, so that the latch may be hooked back out of position for catching the rib on the vertical shaft. The hammer parts and these operating mechanisms are more fully set forth in my application for United States Letters Patent filed on even date herewith and numbered 694,809.

The foot-bar of the treadle that is shown is formed in two sections 28 and 29, the former being joined by arms 30 with a sleeve 31,- loosely mounted upon a rod 32 that is supported by the bed, and the latter being joined by arms 33 with a sleeve 34, loosely mounted upon the same supporting-rod. A lever 35 is connected with the section 28, and this lever,

which is held raised by a spring 36, is connected by a strap 37 with the end of the angle-lever 14, while a lever 38 is connected with the section 29, and to this lever, which is held raised by a spring 39, the end of the catchlever rod 21 is fastened. The meeting ends of the foot-bar sections 28 and 29 so overlap that when the former is depressed the latter is carried down with it, but when the latter is depressed the former is not moved.

-Depressing the foot-bar section 29 of the treadle withdraws the catch-lever and lets the hammer-head drop. During downward movement the hammer-head strikes the finger 23 and turns the rock-shaft, so that the latch 25 is moved from the locking-rib 26 and the vertical shaft 9 released. The spring 15 will then, through the lever 14, hook l3, and arm 12, impart a rotary movement to the shaft 9 and cause the rolls togrip the tail-board and lift the hammer-head. The rising hammerhead engages the cam 16 and rotates the vertical shaft back, so that the grip of the rolls is released and the latch again allowed to engage the lockingrib and hold the shaft with the parts in this position and the spring un der tension. If the section 29 is still depressed, so as to withdraw the catch-lever, the ham mer-head will drop and then again be lifted, which actions will be repeated as long as that section of the treadle is held down and the roll-rotating pulleys are driven.

If it is not desired to have the hammerhead lifted as high as is necessary to be automatically released or if the latch is hooked back, the section 28 of the foot-bar of the treadle may be depressed, and this so moves the lever and vertical shaft that the grip of the rolls on the tail-board is released and the hammer-head allowed to drop. As the section 29 is carried down with the section 28 the catch-lever will not hold the hammer-head up when the section 28 is depressed. When the foot is taken from the section 28, the rolls grip and lift the hammer-head until it is again automatically released and held by the catch-lever or released by another downward movement of: the section 28 of the treadle. By employing the treadle-section 28 as light a blow as desired may be struck, (for the hammer may be released at any height,) and after each depression and release of this section of the treadle the hammer-head is raised and held. If the section 28 is held down, the hammer-head will drop and stay dropped, for with the section 28 down the rolls are moved, so that they do not grip the tail-board.

The foot of the operative may be quickly slipped from the section 28, by means of which the individual blows of varying force may be effected, to the section 29, which may be employed to effect continuous blows of uniform force, and this change is accomplished without requiring the use of the hands of the operative or diverting his attention from the work that he is performing.

I claim as my invention- In combination with the controlling mechanisms of a drop-hammer, a treadle with a foot-bar formed in sections, the outer end of one foot-section being connected with the automatic controlling mechanisms and the outer end of the other foot-section being connected with the foot-controlling mechanisms, said foot-sections extending in the same line and having the inner end of one foot-section overlapping the inner end of the other foot-section, both sections being provided with arms which project toward the end of the hammer and are pivotally connected with the same support, substantially as specified.

FRANCIS A. PRATT.

Witnesses:

HARRY R. WILLIAMS, E. J. HYDE. 

